code: def test_load_graph_from_text(self):
      toy_graph_snap = """#some comment string
                           #some more comment string
                           1\t2
                           1\t3
                           2\t3
                           2\t1
                           3\t1
                           3\t2"""
  
      toy_graph_tsv = """1\t2
                          1\t3
                          2\t3
                          2\t1
                          3\t1
                          3\t2"""
      toy_graph_csv = """1,2
                          1,3
                          2,3
                          2,1
                          3,1
                          3,2"""
  
      temp_fnames = []
      with tempfile.NamedTemporaryFile(
          mode="w", delete=False
      ) as fsnap, tempfile.NamedTemporaryFile(
          mode="w", delete=False
      ) as ftsv, tempfile.NamedTemporaryFile(
          mode="w", delete=False
      ) as fcsv:
          fsnap.write(toy_graph_snap)
          fsnap.file.flush()
          ftsv.write(toy_graph_tsv)
          ftsv.file.flush()
          fcsv.write(toy_graph_csv)
          fcsv.file.flush()
          for fname, fmt in zip(
              [fsnap.name, ftsv.name, fcsv.name], ["snap", "tsv", "csv"]
          ):
              g = load_sgraph(fname, fmt)
              self.assertEqual(
                  g.summary(), {"num_vertices": 3, "num_edges": 6}
              )
              temp_fnames.append(fname)
  
      for name in temp_fnames:
          if os.path.exists(name):
              os.remove(name)
  
imports: from __future__ import print_function
  from __future__ import division
  from __future__ import absolute_import
  from ..data_structures.sgraph import SGraph, Vertex, Edge, load_sgraph
  from ..data_structures.sframe import SFrame
  from .None import util
  import pandas
  from pandas.util.testing import assert_frame_equal
  import numpy
  import unittest
  import tempfile
  import json
  import os
  import sys
  import pytest
label_desc: Use image node_id 9 for calling the GraphTests obj's underlying member method code with example usage: obj.test_load_graph_from_text() without return types